The present invention relates generally to medical devices, and more particularly, to devices for obtaining biopsies, for performing microsurgery and bipolar microelectrocautery. The angle of operation can be varied to permit operation on curved and sloped surfaces.
Conventional instruments for obtaining biopsies from the uterine cervix and the vagina are used, for example, in gynecology for the diagnosis of cervical intraepithelial neoplasia (CIN) which is a non-invasive surface cancer and its precursors. Cervical biopsies of the uterine cervix and of the vagina are common procedures in gynecology.
Cervical biopsies are usually performed after inspection of the cervix through a colposcope (a binocular for magnification and identification of small areas of abnormality). During colposcopic examination, acetic acid is applied on the cervical surface making the area to be biopsied identifiable, even through the unarmed eye, by whitish discoloration. The cervical surface is thereby "mapped out" rather accurately.
However, conventional instrments do not permit an accurate biopsy to be taken. A major disadvantage of conventional instruments is that the angle of the cutting head in relation to the instrument frame cannot be varied and these instruments do not allow access to cervical lesions at variable angles of approach for a directed biopsy. This would be desirable since the lesions commonly are located either on the lateral slope of the cervix or on its slope towards the endocervical canal. Therefore, it can be difficult, if not impossible, to obtain adequate biopsy specimens with conventional instrm ents that take "bites" only in a straight forward direction.
The present invention overcomes this disadvantage by providing an adjustable instrument head with which the angle of operation can be varied to permit operation on curved or sloped surfaces.
Other medical instruments have been suggested in which the relative angle of the foremost part of the instrument is adjustable. However, these instrm ents are not useable or applicable for obtaining biopsies, performing microsurgery or microelectrocautery. Further, a disadvantage of these instruments is that the angle is not easily adjusted while the instrument is being used.
This is a major disadvantage in certain operations, e.g. a laparoscopic procedure, in which a variety of sequential operative functions must be performed. These functions include bipolar electrocautery of surface lesions occupying various surface areas, bipolar electrocautery of violin string adhesions, and bipolar electrocautery of ahesion sheets and sheaths. These adhesions and lesions may be located on various planes since they commonly involve surfaces of the Fallopian tubes and the ovaries which have cylindrical and spheroid surfaces, respectively.
The present invention overcomes this major disadvantage by including an angle adjustment bar that can easily be manipulated to change the angle of the instrument while the instrument is being held and used. Further, angle adjustments can actually be made by squeezing the handles of the instrument. These unique angle adjustment features make the present invention ideally suited for operations with sequential procedures requiring varying angles of approach.
An added disadvantage of most conventional instruments for obtaining biopsies is that they do not possess exchangeable knife blades. Instruments which do have replaceable blades frequently cannot cut through the tissue of the cervix, particularly if it is of relatively firm consistency. The blades of these instruments can actually be bent out of shape during an attempted biopsy.
Instruments with non-exchangeable knife blades require periodic resharpening which means sending the instrument back to the manufacturer, and this creates added expense as well as loss of use of the instrument.